1. Field
One embodiment of the invention relates to a circuit board unit and an electronic apparatus, for example, a circuit board unit and electronic apparatus provided with a heat radiation structure which cools a circuit component.
2. Description of the Related Art
For example, a circuit board unit provided for an electronic apparatus such as a portable computer includes a circuit component such as a cpu. In recent years, semiconductor integration density has dramatically improved, and a calorific value of a circuit component is increasing. In a circuit component having a semiconductor mounted thereon, reliability and life duration are reduced if an operating temperature is very high. Thus, a circuit board unit includes a heat radiation structure which cools this circuit component.
As a heat radiation structure in the circuit board unit, one having a heat pipe and radiation fins combined with each other is well known. One end of the heat pipe is attached on an upper surface of a circuit component which is mounted on a printed circuit board and has a large calorific value. The other end of the heat pipe is extended to a position outside the printed circuit board and connected to the radiation fins. The heat pipe facilitates cooling of the circuit component by transferring heat generated from the circuit component to the radiation fins.
Further, as a heat radiation structure which cools a circuit component, a radiation device including a micro-heat pipe is disclosed in Jpn. Pat. Appln. KOKAI Publication No. 2002-16388. One end of this micro-heat pipe is arranged in contact with a heat generator on a printed board, and the other end of the same is thermally connected with a front panel attached at one end of the printed circuit board. In this radiation device, a portion of the front panel is utilized as a part of a heat sink.
As described above, the radiation structure of the circuit board unit is provided with a heat radiating member such as radiation fins or a radiation plate separately provided from the printed board, and the heat pipe which transfers heat from the circuit component to this radiation member.